Field of the Invention
The present invention relates to a power conversion device for a railway vehicle, and more particularly, it relates to a power conversion device for a railway vehicle including a plurality of radiation fins radiating heat from an apparatus loaded on a railway vehicle at the time of traveling.
Description of the Background Art
A power conversion device for a railway vehicle including a plurality of radiation fins radiating heat from an apparatus loaded on a railway vehicle at the time of traveling is known in general, as disclosed in Japanese Patent Laying-Open No. 2007-13223, for example.
Japanese Patent Laying-Open No. 2007-13223 discloses a power conversion device for a railway vehicle including a plurality of coolers (radiation fins) used for a power conversion device for driving a vehicle set in an underfloor space of a railway vehicle. In the power conversion device for a railway vehicle disclosed in Japanese Patent Laying-Open No. 2007-13223, coolers (radiation fins) are arranged on the lower surface of the body of a box-shaped power conversion device in a state divided into three along the traveling direction of the vehicle. Traveling wind resulting from traveling of the railway vehicle is supplied to the cooler positioned on the most windward side and successively supplied to the coolers provided at the rear stage (on the downstream side), thereby radiating (discharging) heat from the coolers to the open air (atmospheric air).
In the power conversion device for a railway vehicle described in Japanese Patent Laying-Open No. 2007-13223, however, air warmed by drawing heat from the cooler (radiation fin) provided on the upstream side in the traveling direction of the vehicle (on the windward side in the traveling wind) is conceivably successively supplied to the adjacent coolers provided on the downstream side (at the rear stage). In this case, the cooler positioned on the most windward side exhibits an excellent cooling performance through heat exchange with fresh air having a relatively low temperature, while the cooling performances (radiation performances) of the remaining two coolers provided on the downstream side are lowered as compared with that of the cooler provided on the upstream side due to successive heat exchange with the air (having a higher temperature higher than the fresh air) warmed by drawing heat from the cooler provided on the upstream side. Therefore, the cooling performances (radiation performances) of the individual coolers (radiation fins) are disadvantageously dispersed.